Kare no Ai wa Kanojo o Kowasu

Hatori Mio has lost both her parents and step-parents.
Hatori Takara, her elder step-brother, showers her with love to the point of abnormality.

December 23rd. With Christmas drawing near, Hatori Mio was eating lunch with her friend at university, as usual.
Her friend, Mayu, invites her to a year-end party...
This is a story that happens from that one scene.

[Translated from the official website]